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991.
992.
Solitary thyroid nodule: diagnosis and management 总被引:1,自引:0,他引:1
E L Mazzaferri E T de los Santos S Rofagha-Keyhani 《The Medical clinics of North America》1988,72(5):1177-1211
Thyroid nodules are common. Most are benign lesions since clinically important thyroid carcinoma is a relatively rare disease. The most sensitive and specific test for the diagnosis of thyroid cancer is fine-needle aspiration biopsy, but its diagnostic accuracy depends upon whether or not one excises all suspicious nodules, thus including them as correctly diagnosed. Nevertheless, fine-needle aspiration biopsy is the most sensitive, specific, and cost-effective test for thyroid cancer. Therapy depends upon the cause of the thyroid nodule. 相似文献
993.
994.
Detection of Epstein Barr virus in an hepatic leiomyomatous neoplasm in an adult human immunodeficiency virus 1-infected patient 总被引:5,自引:0,他引:5
S. Prévot J. Néris P. P. de Saint Maur 《Virchows Archiv : an international journal of pathology》1994,425(3):321-325
We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient. 相似文献
995.
W. de Riese E. B. Walker C. de Riese T. M. Ulbright W. N. Crabtree J. Messemer J. A. Jones A. Hinkel R. S. Foster J. P. Donohue T. Senge 《Urological research》1994,22(4):213-220
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only. 相似文献
996.
Human xenoreactive natural antibodies of the IgM isotype activate pig endothelial cells 总被引:1,自引:0,他引:1
Abstract: Preformed, xenoreactive natural antibodies (XNA) and complement (C) are involved in the initiation of vascular rejection of organs transplanted between discordant species, presumably by stimulating donor organ endothelial cells (EC). Although C is known to play a role in the activation of EC, it has not been clear whether the antibodies serve only to anchor the initial components of C, and thus permit the C cascade to proceed, or whether the antibodies themselves deliver a signal to the EC. We have tested affinity-purified human IgM containing XNA (IgM-XNA) for its ability to stimulate in vitro the up-regulation of genes in pig EC. Northern blot analysis shows that IgM, which contains XNA, stimulates mRNA accumulation for certain genes (including IL-8, PAI-1, and ECI-7, a new gene that we have found is associated with EC activation), but not others known to be up-regulated in response to TNF, IL-1 or LPS. Our results show that XNA provide a signal to EC, and thus may themselves participate in activation of EC and consequent vascular rejection. 相似文献
997.
998.
We studied the immunocytochemical characteristics of the ballooned neurons (BN) in three patients with cortical degeneration with neuronal achromasia (CDNA) using antibodies to phosphorylated neurofilaments (PNF), tau, Alz-50, ubiquitin, beta (A4) amyloid, and glial fibrillary acidic protein. All BN exhibited intense perikaryal staining for PNF protein. Most BN and some normal-appearing neurons also stained for ubiquitin and Alz-50. The BN did not immunostain for tau protein, and none of the cases had tau-reactive neocortical neurofibrillary tangles or Pick bodies. One case had occasional senile plaques that stained for beta amyloid; no case had amyloid angiopathy. Our findings suggest that the pathophysiologic basis of the cortical degeneration in CDNA involves an alteration of neuronal cytoskeletal metabolism affecting neurofilament and possibly microtubular proteins in conjunction with activation of the ubiquitin proteolytic system. 相似文献
999.
Recent studies with standardized laboratory measurements of skin blood flow suggest an influence of female sex hormones on vasospasm. Therefore we evaluated the influence of sex hormonal status on the subjective complaints of Raynaud's phenomenon and furthermore the combined presence of Raynaud's phenomenon and migraine. A detailed questionnaire was filled in by 130 primary Raynaud patients (31 males, 99 females), while 27 females, with regular menstrual cycles without the use of oral contraceptives, kept a diary with daily registration (during three months) of frequency, severity and duration of the vasospastic attacks. Complaints improved during pregnancy in 6 out of 23 females. No influence of the menopause or the use of oral contraceptives was found. An exacerbation in some phases of the menstrual cycle was present in 15 out of 80 females. The diaries, however, did not show such influence of menstrual cycle phase. Migraine was present in 21% of the Raynaud patients. In contrast to most reports in the literature and contrary to the results of laboratory research, this study shows that most females do not experience an important subjective influence of sex hormonal status on vasospastic attacks. 相似文献
1000.
E. Van de Keift K. De Boulle P. Willems J. -J. Martin P. Selosse B. Van der Auwera 《Acta neurochirurgica》1992,117(3-4):172-177
Summary Inactivation of tumour suppressor genes or anti-oncogenes as well as activation of dominant acting oncogenes seem to be important mechanisms in the pathogenesis of gliomas. We compared constitutional and tumoural genotypes at different restriction fragment length polymorphism loci (RFLP) on chromosomes 10 and 17 in 15 unrelated individualsLoss of heterozygosity (LOH) pointing to chromosomal loss or deletions was detected for at least one chromosme 17 marker in 11 gliomas (astrocytomas grades I–III and glioblastoma multiforme), whereas LOH for chromosome 10 loci was only detected in 3 out of 9 cases of glioblastoma multiforme and was not detected in low grade gliomas. Since LOH for chromosome 10 loci seems to be restricted only to glioblastoma multiforme, it is possible that recessive mutations on chromosome 10 are engaged in tumour progression from astrocytomas to glioblastoma multiforme. As LOH of chromosome 17 markers occurs in astrocytomas as in glioblastoma multiforme, chromosome 17 loci probably are involved in early tumour development. 相似文献